Thousands of Oakland residents pass through “Light Up,” the large yellow sculpture in Posvar Hall Plaza, on their way to classes or meetings everyday, not thinking twice about it. But on Thursday, it was the center of attention.

As the cool autumn air whisks its way into Pittsburgh and strips away the amber foliage, the taxi-yellow sculpture that sits between Posvar Hall and Hillman Library seems to shine even more brightly. But what exactly is this mysterious sculpture?Possible answers as to its identity range from awkward gir...